Nowadays, the network of SDN (Software-defined networking) has many advantages, so it is gradually used by enterprises and institutions. SDN is a network virtualization and uses Open Flow to separate the control plane of a router from the data plane, and is implemented with software. SDN allows a network administrator, without a change of the hardware, to replan the network by means of a program in a central control manner, so that the network can control paths automatically (automation). In the new control mode, a controller of a control layer is responsible for the network administration instead of the original, providing a method for controlling the network traffic and providing a core network and an innovative good network platform. However, this storage server under SDN only supports SATA hard disks or IP hard disks. The user is unable to choose a hard disk interface on the same storage server freely. This storage server cannot meet the demand of the user. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems and to develop a server capable of supporting and automatically identifying an IP hard disk and a SATA hard disk for the user to select a hard disk interface on the same storage server freely.